如何在二维中找到中心点周围的所有点

Question

我有中心点 x: 0 和 y: 0。

如何让所有点的距离达到 5？

我的代码并不完美：

function getPoints(startX, startY, distance) {
    var res = []
    for (var i = 1; i < distance; i++) {
        res.push({ x: startX + i, y: startY })
        res.push({ x: startX - i, y: startY })

        res.push({ x: startX, y: startY + i })
        res.push({ x: startX, y: startY - i })

        res.push({ x: startX + i, y: startY + i })

        res.push({ x: startX - i, y: startY - i })
    }
    console.log(res)
    console.log(res.length)
}

getPoints(0, 0, 3)

Answer 1

伪代码（对于您的情况，R=5）​​

for dy = 0 to R
  for dx = 0 to Floor(Sqrt(R*R - dy*dy))
  // or dx = 0
  // while dx*dx+dy*dy<=R*R do 
      put startX + dx, startY + dy 
      put startX - dx, startY + dy      
      put startX + dx, startY - dy 
      put startX - dx, startY - dy      
    //dx++

如果你需要正方形，代码很简单：

for y = centerY - size to centerY + size
  for x = centerX - size to centerX + size
     put x, y